Whats the longest usb cable you tested with? I'm thinking about putting the cards in a different room for heat reasons. I'm thinking of 15 foot cables.
I have 2m and 3m cables, but I haven't had a chance to test them yet. I'll update this thread when I do.
1M version are working fine for 4 days now without any problem.
Been wondering about this as well. Looking at setting up a full 42U rack setup with all the MB's on the bottom, and all the GPUs on the top.